1. Field of the Invention
The present invention relates to a permanent magnet pump motor having a permanent magnet rotating electric machine that includes a rotor and a stator, and a permanent magnet pump motor system incorporating the same.
2. Description of the Related Art
Widespread dissemination of permanent magnets and inverters that offer enhanced performance in recent years has prompted momentum toward incorporation of permanent magnet rotating electric machines that can achieve reduction in size and greater efficiency. A need also exists for variable speeds of motors in order to reduce environmental load.
Against this background, with a view to application to LNG pump motors, motors that incorporate permanent magnets are being developed from existing induction motors. The rotor in a permanent magnet rotating electric machine is magnetized at all times and, particularly when the rotor is to be inserted in the stator, a measure needs to be taken for considering a magnetic attractive force. Various forms of structures and devices are being studied in order to insert the rotor into the stator or separate the rotor from the stator.